Disillusioned with RT-AC86U (and RT-AX86U)

[MarkyPancake]

My settings are:

<snip>

I've left most at defaults, and only changed a few settings based on recommendations. Have I missed any significant ones?

Quite a few professional settings enabled on the 2.4 GHz band that don't have a good effect on wireless performance in my experience. These are the only professional settings I have enabled on both the 2.4 and 5 GHz bands on my AC86U:

• AMPDU RTS
• Enable WMM
• Enable WMM APSD
• Modulation Scheme set to MCS 7 (802.11n) on 2.4 GHz and MCS 9 (802.11ac) on 5 GHz (I've experimented with the higher non-standard options and saw various issues with different devices)

With these settings, devices consistently achieve the max speeds they're capable of on each band and on the 5 GHz network they max out our 200 Mbps down / 20 up service.

 

[TheMegaMan]

100Mbps, maybe, in optimal conditions. Certainly not guaranteed with a USB drive in USB 3.0 mode.

Does the 2.5GHz band respond as expected when not using any USB drives? How about when the USB on the router is in USB 2.0 mode?

If none of the above helps...

Your environment isn't optimal, obviously.

At this point, I would redo the full reset. Then, after verifying that the suggested defaults are working, slowly add (1 feature, option, script) at a time, and keep excellent notes. This may be the only way to track your issue down.

Myself, at the minimum, I would:

• Fully Reset Router and Network
• Fully Reset / Best Practice Setup / More (best practice defaults).
• New, never before used SSIDs (8 alphanumeric characters)
• Passwords (16 alphanumeric characters)
• Add your client devices in a systematic order (write it down) and as slowly/controlled as possible.
• Add features, options, scripts (one at a time)

If the 2.5GHz interference is permanent at your location, you may need to find/use only 5GHz devices going forward.

100Mb/s optimal? I'd be expecting >200Mb/s in optimal conditions. 100Mb/s should achievable in reasonable real-world conditions. But whatever, I'm currently an order of magnitude below this. While I can't say I had measured it before these issues and I can't quantify it, it certainly *felt* as fast on 2.4GHz as it feels on 5GHz. Today, it's noticeably/significantly slower on the 2.4GHz band. The important point here is that it used to be fine. It's only the last month or two that it's got slow, so something has changed in my environment, and I'm 90% sure it's nothing I changed in my router config.

@OzarkEdge had already raised a potential problem with USB 3.x, so I reduced this to 2.0 and then removed the USB drive completely, and it made no difference to the internet speed tests I was doing at the time. Transferring data from a USB drive in the router to a PC is about as direct a measurement of the wireless bandwidth achieved, wouldn't you agree?

FYI, reducing the interface to USB2 maxed out the transfer on 5GHz to around 40MB/s (down from 50MB/s on USB3, where it was probably limited by the wifi, not the USB interface), but made no difference to the 2.4GHz transfer speeds (still averaging just over 1MB/s, but wavering between 500kB/s and 2.5MB/s - very unstable).

You haven't commented on the wireless settings I've got. As far as I am aware, these are in accordance with the mythical best practice settings. So do I take it that I've not done anything obviously stupid with this, so I need to leave the router alone and be looking at something elsewhere?

 

[Tech9]

100Mb/s optimal? I'd be expecting >200Mb/s in optimal conditions. 100Mb/s should achievable in reasonable real-world conditions.

No way. You have wrong expectations. In busy environments you'll be lucky to get 40Mbps on 2.4GHz. This is what I get in my downtown apartment, maximum. In my house I can see 90Mbps on 2-stream clients, 50Mbps on 1-stream. I use 20MHz wide channel like everyone else around.

 

[TheMegaMan]

Quite a few professional settings enabled on the 2.4 GHz band that don't have a good effect on wireless performance in my experience. These are the only professional settings I have enabled on both the 2.4 and 5 GHz bands on my AC86U:

• AMPDU RTS
• Enable WMM
• Enable WMM APSD
• Modulation Scheme set to MCS 7 (802.11n) on 2.4 GHz and MCS 9 (802.11ac) on 5 GHz (I've experimented with the higher non-standard options and saw various issues with different devices)

With these settings, devices consistently achieve the max speeds they're capable of on each band and on the 5 GHz network they max out our 200 Mbps down / 20 up service.

Thank you! That's the kind of list I was hoping to see - what features users have found that work for them, or what combinations jsut don't work.

I've just adjusted the settings to match your suggestion. Still doesn't seem to have had a positive effect yet, but I'll let it settle for a while to see if it picks up a bit overnight.

Any comments on other parameters like the RTS Threshold or Preamble length?

It does seem crazy and sad that the router manufacturers produce hardware to support all these wonderful features to improve bandwidth, and the only settings that seem to work are switching nearly everything off. I am thinking I've actually wasted my money on an AX router if I need to disable wifi6 to make it work with older equipment, and not just because it seems there was nothing wrong with my AC86, after all. I suppose I can at least use both routers (the AC86 as a legacy AP and the AX86 in AX mode as the high performance AP). Sorry to rant. I'm sure this isn't just an Asus problem and is the price for wanting backwards compatibility, but it's a shame the protocols aren't cleaner with respect to interactions with older versions.

 

[TheMegaMan]

No way. You have wrong expectations. In busy environments you'll be lucky to get 40Mbps on 2.4GHz. This is what I get in my downtown apartment, maximum. In my house I can see 90Mbps on 2-stream clients, 50Mbps on 1-stream. I use 20MHz wide channel like everyone else around.

But I'm not in a busy environment. I'm on the edge of a village. And I'm barely getting 10Mb/s. As I said, I can't state what I got before the problems started, but it *felt* like an order of magnitude better than I'm getting now on 2.4GHz.

 

[TheMegaMan]

Does anyone know how to interpret these graphs from the 'Advanced Troubleshooting' tool in the Merlin firmware? These CRS 'glitch' figures on 2.4GHz are around 500 times higher than the equivalent graphs for 5GHz. What are CRS, PLCP and FCS?

 

[Tech9]

Disable Bluetooth Coexistence and all Beamforming. Use the channel with higher available throughput according to Wi-Fi Analyzer in Asuswrt-Merlin, not necessarily 1-6-11. Try again.

 

[shoman94]

I get about 75 to 100mbps. Please be careful when giving speeds because there is a big difference between Mbps and MBps.

I have never seen higher than 105mbps on my AC88u I would think yours would perform about the same since wifi4 is an old tech. I'm wondering if you have a real old device bogging your 2.4? Do you have something that's wireless b or g still?


Edit; Official firmware just released on your AX86U

 

[TheMegaMan]

I get about 75 to 100mbps. Please be careful when giving speeds because there is a big difference between Mbps and MBps.

I have never seen higher than 105mbps on my AC88u I would think yours would perform about the same since wifi4 is an old tech. I'm wondering if you have a real old device bogging your 2.4? Do you have something that's wireless b or g still?


Edit; Official firmware just released on your AX86U

Sounds reasonable. Yes, I think I've got my bits and Bytes correctly listed. I was getting 1MB/s or 10Mb/s download speeds from the router's USB stick. I'd be delighted with 10MB/s...even 5MB/s might stop my devices from dropping out.

Resetting the SSID to chuck all my smart sockets, echo devices, etc, off the network, I'm now seeing my PC as the only 2.4GHz client, and....I got a download speed of 3.5MB/s! Woohoo, I thought...then it slowed right back down to 1MB/s for the last couple of minutes of the transfer.

So I think this rules out it being a very old device bogging down the network, as none are connected at the moment.

Ah, thanks...just tried to download the new firmware, but getting a 404 error - I guess it's not *quite* released yet! :-D Will try it when I can.

I think I'm getting more and more convinced it's some external interference source that's causing this. The speed varies so much although it's never as high as I'm sure it used to be. But I don't see how I can make any further progress with this. I guess I'll just have to try and migrate everything over to 5GHz when I can....maybe get some 5GHz bridges and use cables to hook up my older devices that only support 2.4GHz wifi (that need the speed/stability that I don't currently have).

Anyone know of any suitable bridge devices?

Oh, and I just copied all your settings (apart from the Roaming Assistant) - no improvement, unfortunately. Although @L&LD is going to tell me I need to do a nuclear reset before I can expect any of them to actually do what they're supposed to do. Is there anywhere which actually explains what each of these features is supposed to do, and in what circumstances each can or should be enabled or disabled? I assume Asus know this stuff...

 

[shoman94]

Sounds reasonable. Yes, I think I've got my bits and Bytes correctly listed. I was getting 1MB/s or 10Mb/s download speeds from the router's USB stick. I'd be delighted with 10MB/s...even 5MB/s might stop my devices from dropping out.

Resetting the SSID to chuck all my smart sockets, echo devices, etc, off the network, I'm now seeing my PC as the only 2.4GHz client, and....I got a download speed of 3.5MB/s! Woohoo, I thought...then it slowed right back down to 1MB/s for the last couple of minutes of the transfer.

So I think this rules out it being a very old device bogging down the network, as none are connected at the moment.

Ah, thanks...just tried to download the new firmware, but getting a 404 error - I guess it's not *quite* released yet! :-D Will try it when I can.

I think I'm getting more and more convinced it's some external interference source that's causing this. The speed varies so much although it's never as high as I'm sure it used to be. But I don't see how I can make any further progress with this. I guess I'll just have to try and migrate everything over to 5GHz when I can....maybe get some 5GHz bridges and use cables to hook up my older devices that only support 2.4GHz wifi (that need the speed/stability that I don't currently have).

Anyone know of any suitable bridge devices?

Have you tried a different device than your PC to rule that out?

 

[L&LD]

Non-Wi-Fi interference.

Test all: Move your router. Antennae, and change the router orientation as much as possible. Get a 50' or 100' Cat5e Ethernet cable to put the router on the other side of the house (if you can). Nothing else to do here, short of trying a new router with a default configuration and/or moving to a new property.

 

[TheMegaMan]

Have you tried a different device than your PC to rule that out?

Yeah, laptop PC was slightly better than desktop, but still slow (less than 20Mb/s) in a similar location.

Bloody wireless.

 

[Zardoc]

Specifically Asus firmware, not Merlin?

My settings are:

View attachment 36573

View attachment 36574
View attachment 36575

I've left most at defaults, and only changed a few settings based on recommendations. Have I missed any significant ones?

Hi,

I tried your professional settings and lost 60 speed. I went from 115 to around 50. I would try to use default just to test. Sometimes to much tweaking, well, is too much

 

[TheMegaMan]

Hi,

I tried your professional settings and lost 60 speed. I went from 115 to around 50. I would try to use default just to test. Sometimes to much tweaking, well, is too much

Hmmm. You're still getting a lot higher performance than I am. I'll try another full reset in the next few days, as one last try. Did you make *any* changes from the defaults, ie. did you separate the bands, reset the SSIDs or anything else?

I've been adding 5GHz bridges to a few of my higher bandwidth clients that only support 2.4GHz internally, but have an ethernet socket. That's avoided the problem for those.

 

[TheMegaMan]

I thought I'd run another test on 2.4GHz today, just for the sake of it. I've not made any changes to the router since last week. And I'm now getting over 45Mb/s. That's more like how it used to be! So whatever was causing the problem seems to have gone away. Most odd. I have now moved a few clients over to the 5GHz band, but that hadn't made any difference to the issues on 2.4GHz when I did that last week, so I don't think it's a case that one of those had 'gone rogue' on 2.4GHz. Of course, those devices have been a lot faster and more reliable since I changed them.

Anyway, I think that while my settings might not be optimal, they (alone) are not the cause of this issue. I just wish I knew what it was. Maybe a neighbour has switched off their wifi jammer...

 

[L&LD]

Aren't you glad you didn't 'drop the Asus in the bin' then?

 

[TheMegaMan]

I'm glad I didn't waste a lot of time immediately doing yet another nuclear reset that it turns out wasn't needed.

 

[L&LD]

A 'nuclear reset' is rarely a waste of time. Doing nothing for over three weeks isn't a solution either. And I did suggest the nuclear reset after you had spent two weeks already without success.

Glad your network is semi-behaving for you now.